Conference Papers

A one-dimensional model capable of simulating flood wave propagation in a river or network of channels is presented. The computer model is programmed to provide maximum flexibility in the adaptation of channel geometry, the specification of conveyance properties, and the treatment of boundary conditions. An equation transformation procedure is employed in the model to minimize computer...

The Complex Variable Boundary Element Method (CVBEM) offers an effective and efficient means for modeling two-dimensional potential and related flow problems. The method has been applied to various hydraulic and hydrodynamic problems - surface water, ground water, and other flows - and has proven its accuracy, reliability and usefulness. The paper describes the CVBEM and its application.

Remote sensing from satellites provides a unique tool to measure the parameters of the Earth on a worldwide scale. A number of organizations are currently engaged in, or proposing to embark on, worldwide measurement/monitoring programs. Program objectives vary in type and complexity, including a form of technical library and an ambitious experiment to validate algorithms to derive land...

An ongoing program to monitor the hydrothermal system in Long Valley for changes caused by volcanic or tectonic processes has produced considerable data on the water chemistry and discharge of springs and fluid temperatures and pressures in wells. Changes in hot spring chemistry that have been recorded probably relate to interactions between the variations in the quantity of liquid and...

National Water Information System (NWIS) has been designed as an interactive, distributed data system. It will integrate the existing, diverse data-processing systems into a common system. It will also provide easier, more flexible use as well as more convenient access and expanded computing, dissemination, and data-analysis capabilities. The NWIS is being implemented as part of a...

Highly acidic contaminated water is moving through a shallow aquifer and interacting with streams near Globe, Arizona. Dissolved concentrations reach 3,000 mg/L iron, 150 mg/L copper, and 16,400 mg/L total dissloved solids; pH is as low as 3. 6. Samples from 16 PVC-cased observation wells include uncontaminated, contaminated, transition, and neutralized waters. Chemical reaction with...

Five reports dealing with flood magnitude and frequency in urban areas in the Southeastern United States have been published during the past 2 years by the U. S. Geological Survey. These reports are based on data collected in Tampa and Tallahassee, Florida, Atlanta, Georgia, and several cities in Alabama and Tennessee. Each report contains regression equations useful for estimating flood...

The U. S. Geological Survey has previously experienced the impacts on the National Mapping Program that are associated with implementing a readjustment of the horizontal datum. The impacts of these past readjustments were minimal compared to those of the current readjustment. The Geological Survey currently has produced and published over 60,000 different map products. The 7. 5-minute...

Fine sediment in channels, rivers, estuaries, and coastal waters undergo several physical processes including flocculation, floc disruption, deposition, bed consolidation, and resuspension. This paper presents a conceptual model and reviews mathematical models of these physical processes. Several general fine sediment models that simulate some of these processes are reviewed. These...

Flow data were obtained in the surf zone across a barred profile during a storm. RMS cross-shore velocities due to waves in the intragravity band (wave periods greater than 20 s) had maxima in excess of 0. 5 m/s over the bar crest. For comparison to measured spectra, synthetic spectra of cross-shore flow were computed using measured nearshore profiles. The structure, in the infragravity...

The U. S. Geological Survey (USGS) is the lead civilian mapping agency in the United States and is responsible for creating and maintaining numerous map series. In Alaska the standard topographic map series is at a scale of 1:63,360, and maps at that scale have been available from the USGS since the late 1940's. In 1981 USGS initiated production of orthophotoquads of Alaska, also at a...

The change in permeability with time of granite, quartzite, anorthosite and gabbro was measured while these rocks were subjected to a temperature gradient. Permeability reductions of up to two orders of magnitude were observed, with the greatest reactions occurring in the quartzite. These changes are thought to be caused by dissolution of minerals at high temperatures, and redeposition...